Product of poet — Frost, by the sound of it (5)
I believe the answer is:
rhyme
'product of poet' is the definition.
'frost by the sound of it' is the wordplay.
'frost' becomes 'rime' ('rime' can be a synonym of 'frost').
'by the sound of it' indicates a 'sounds like' (homophone) clue.
'rime' is a homophone of 'RHYME'.
(Other definitions for rhyme that I've seen before include "Poem, eg for nursery" , "Verse, doggerel" , "Short piece of verse" , "Without reason or . . . . . - makes no sense" , "Short poem" .)